From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Salsano Subject: Re: [PATCH] netem/iproute2 solving correlated loss issues [2/5] Date: Sat, 19 Dec 2009 10:48:29 +0100 Message-ID: <4B2CA16D.4090801@uniroma2.it> References: <4B2B5A26.8050400@uniroma2.it> <4B2B6676.301@yahoo.it> <20091218093605.76903fe5@nehalam> <20091218.200158.112585402.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: shemminger@vyatta.com, fabio.ludovici@yahoo.it, netdev@vger.kernel.org To: David Miller Return-path: Received: from smtp.uniroma2.it ([160.80.6.16]:57250 "EHLO smtp.uniroma2.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751095AbZLSJsd (ORCPT ); Sat, 19 Dec 2009 04:48:33 -0500 In-Reply-To: <20091218.200158.112585402.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: David Miller wrote: > I would like some kind of commit message which at least > explains what in the world this stuff is, how it works, > why we want it etc. > you're right we will put this information in the commit messages, some hints hereafter: starting from the consideration that the model for generating correlated loss is broken in current netem (as for example described in https://lists.linux-foundation.org/pipermail/netem/2007-September/001156.html) we have implemented a more general loss model the patch allows to generate loss patterns according to a determinist pattern that can be given as input: tc qdisc add/change dev eth0 root netem loss_pattern filename or according to different loss models including the ones commonly used in the literature (bernoulli, gilbert, gilbert-elliot...) tc qdisc add/change dev eth0 root netem loss_bern p tc qdisc add/change dev eth0 root netem loss_gilb p r [1-h] tc qdisc add/change dev eth0 root netem loss_gilbell p r [1-h [1-k]] tc qdisc add/change dev eth0 root netem loss_GI ploss [burst_length [density [pisol [good_burst_length]]]] tc qdisc add/change dev eth0 root netem loss_GI_tran p13 p31 [p32 p23 [p14]] tc qdisc add/change dev eth0 root netem loss_gilb_4s p r [1-h] tc qdisc add/change dev eth0 root netem loss_gilbell_4s p r [1-h [1-k]] (full explanation is reported in http://netgroup.uniroma2.it/twiki/bin/view.cgi/Main/NetEm2) -- ******************************************************************* Stefano Salsano Dipartimento Ingegneria Elettronica Universita' di Roma "Tor Vergata" Via del Politecnico, 1 - 00133 Roma - ITALY http://netgroup.uniroma2.it/Stefano_Salsano/ E-mail : stefano.salsano@uniroma2.it Cell. : +39 320 4307310 Office : (Tel.) +39 06 72597770 (Fax.) +39 06 72597435 *******************************************************************